1. Field of Invention
This invention relates to a pressure sensor, and more particularly to a semiconductor pressure sensor for sensing absolute pressure.
2. Description of Related Art
In the field of pressure meters, semiconductor pressure sensors are increasingly being used more frequently. In known pressure sensors, for example, sensors for sensing relative pressure, a silicon diaphragm forms the core of the component, in which, through ion implantation, resistive paths are generated. If pressure is exerted on the diaphragm, it is mechanically depressed. The pressure exerted on the diaphragm causes resistive changes in the diaphragm due to piezoresistive effects. The piezoresistive effects are utilized in order to convert physical pressure into an analog electrical signal. Pressure sensor chips can be built into casings which consist of metal and have an aperture in the cover for transmitting the ambient pressure to the pressure-sensitive chip surface. Such casings are relatively expensive and cumbersome.